Removable/refillable ink cartridges are commonly used for supplying liquid ink to electrographic imaging devices. Some electrographic imaging devices may maintain a positive pressure of liquid ink, carrier and/or printed down ink at the cartridge interface even when the cartridge is removed. To accommodate such replaceable ink cartridges, an interconnect must be provided that enables the cartridge to be easily and reliably replaced, while preventing liquid ink from leaking from the imaging device or the cartridge. One source of leakage is the physical interface of the interconnect.
U.S. Pat. No. 5,546,984 (Arcaro) discloses a bellows type, low spillage, quick disconnect unit for an electrophotographic printer. A bellows concentrically surrounds a plunger and extends from an inlet housing to an expanded tip of the plunger. The bellows has an engagement end that rubs against the expanded tip, thereby sealing the interior of bellows from the external environment. No seals are disclosed to prevent fluid from collecting on the expanded tip.
U.S. Pat. No. 5,461,466 (Girard et al.) discloses a dripless seal for a liquid toner cartridge that utilizes a foam material to absorb any excess fluid that remains on the external face of the fluid coupling. Again, no seals are disclosed to prevent fluid from collecting at the valve interface.
Therefore, what is required is an improved, self-sealing valve assembly that minimizes dripping and leakage during multiple engagement and disengagement cycles of a removable ink cartridge to an imaging device.